In general, when a semiconductor device is manufactured, a photoresist is coated on a substrate such as a semiconductor wafer, the thus formed resist film is exposed in accordance with a predetermined circuit pattern, and the exposed pattern is developed so as to form a circuit pattern in the resist film.
In this photolithographic step, there is generally used a system in which an exposure apparatus is connected to a coating and developing apparatus for coating and developing a resist.
As a conventional developing apparatus, there has been known, for example, a rotational developing paddle type in which a developer is supplied to a substrate which is being rotated, the developer is spread out over all the substrate, a developer is then supplied from a part near a center of the substrate while the rotational speed of the substrate is decreased, and a developer film (paddle) is formed by the accumulated developer.
In such a developing apparatus, there has been known a method in which a deionized water is supplied to a surface of a substrate before the developing process, in order to improve a wetting property (see, for example, JP 2005-210059 A).
Meanwhile, in order to cope with further miniaturization of a device pattern and further thinning of a film, there is an ongoing demand for raising a resolution of exposure. As one of the methods for raising the resolution of exposure, there is known an immersion exposure method in which a substrate is exposed with a light-transmittable liquid layer being formed on a surface of the substrate, in order to raise the resolution by improving an exposure technique by an existing light source such as argon fluoride (ArF) light source. In this immersion exposure technique, under the condition that a liquid film of a deionized water is formed between a lens and a surface of a substrate, a light ray emitted from the light source passes through the lens and transmits the liquid film so as to be irradiated on the substrate, whereby a predetermined resist pattern (circuit pattern) is transferred to the resist.
In the liquid exposure technique, a highly water-repellent resist (non-topcoat resist) is sometimes used, or a highly water-repellent protective film (upper protective film) is sometimes used on a resist. In order that a deionized water is stabilized lest droplets of the deionized water remain on a substrate so as to improve a productivity, there is used the non-topcoat resist that does not require the upper protective film.
For example, since the non-topcoat resist is highly hydrophobic, even when a deionized water is supplied to a substrate surface before the developing process by using the technique described in JP 2005-210059 A, a surface of the resist film cannot obtain a sufficient wetting property. As a result, the developer on the substrate is repelled and spun off. Thus, there is a problem in that it is difficult to form a developer film (paddle) on the substrate surface even when a supply amount of the developer is increased.